Teachers and principals from three school districts were interviewed concerning their assumptions and beliefs about the basis for pupils' underachievement and about their own roles in delivering special education to pupils. Interviews covered the topics of identification, prereferral and assessment procedures, programming both prior to and following placement of pupils in special education programs, ongoing evaluation and review procedures, and communication among staff and with parents Responses were coded on a 7-point scale to reflect a "restorative" (i.e., deficit-centered) vs. a "preventive" (i.e., program-centered) viewpoint, on each of the topics. Results indicated that belief systems were consistent within individuals, and varied widely within and across teaching roles. A significantly higher proportion of principals than of regular classroom and subject teachers were rated as holding preventive beliefs, while the proportions of resource teachers and segregated class special education teachers rated as preventive were ranked between those of principals and regular teachers. Correlations between members of a school staff were for the most part significant, suggesting a peer influence on stated beliefs and assumptions. The operational definition of belief systems presented here offers a tool for examining teachers' beliefs about their responsibilities toward exceptional children and the factors that influence these beliefs.

A longitudinal study was conducted of 118 children with severe and profound hearing losses-Children were first tested when they were between 3 and 5 years and again in 3 or 4 years, using measures of receptive and expressive spoken language, receptive language in the child's primary educational modality, receptive and expressive mother-child communication, and social development. A multivariate design was used to investigate the effects of age of intervention, program intensity, and parent instruction on the children's linguistic and social development. Early intervention was associated with higher receptive language scores in the first, but not in the final year. Age of intervention was not related to any other language measure or the measure of social development. Consistent effects were not associated with program intensity or parent instruction.

A longitudinal study was conducted of 139 children with severe and profound hearing losses. The children were between 3 and 5 years of age at the commencement of the 4-year study. The relationship of several background and educational variables with the linguistic, academic, and social development of the children was investigated. Age, hearing loss, and intelligence were related to most of the dependent measures. Relationships involving communication mode (auditory/oral vs. total communication) varied with the measure being considered. The variable of program type (individual vs. group) interacted with the degree of hearing loss and with communication mode. Although early intervention was related to certain dependent measures, no relationships were found that involved direct instruction by parents or integration.

A longitudinal study was conducted of the effect of mothers' communication mode on the language development of 149 children with severe and profound hearing losses. The relationship of several subject and family characteristics to mode selection was also investigated. The children were between 3 and 5 years of age at the commencement of the 4-year study. Mothers' mode was coded from videotapes of structured and semistructured interactions. Findings indicated that children whose mothers used oral communication had higher scores on measures of spoken language, whereas children whose mothers used manual communication had higher scores on measures of receptive language and mother-child communication. Within the oral group, children whose mothers made extensive use of gestures had lower scores than children whose mothers did not. Within the manual group, children receiving limited sign input had lower scores on most measures than children receiving extensive input.

The kingdom of Luba Lomami was enlarged and strengthened by the conquest of Kalala Ilunga at an unknown date before the end of the sixteenth century. It became a large but not dominant state. The expansion of Luba Lomami is generally considered to have occurred in the early eighteenth century, as a delayed consequence of the Kalala Ilunga conquest. In this it is said to have been paralleled by the expansion of Lunda. Unlike Lunda, however, it is supposed to have suffered from severe structural deficiencies. These, it has been argued, inhibited its further expansion and, in the mid-nineteenth century, caused it to disintegrate.It is suggested here, however, that the expansion of Luba Lomami did not occur until the late eighteenth or early nineteenth century. This expansion coincided with the extension of the Bisa trading system into the chiefdoms south-east of Luba Lomami and was designed to capture this trade. Later conquests in the south may have been related to the development of Nyamwezi and Bihe trading systems. However, the principal motive for further expansion was the need to capture new sources of ivory and, to a lesser extent, slave-yielding lands. Luba Lomami's success can be attributed to its proximity to the Bisa trade route, its relatively centralized political structures, the availability of viable areas of expansion, and the existence of suitable mechanisms to incorporate the conquered chiefdoms. In the first half of the nineteenth century Luba Lomami subjected most of the area between the Lubilash and Lake Tanganyika and between the forest and the copper belt.In about 1870 the terms of the long-distance trade turned against Luba Lomami. New traders arrived carrying guns. Luba Lomami could not match the new techniques for it no longer had the resources with which to purchase guns. Its own resources of ivory and slaves were exhausted. It could no longer obtain supplies by expansion, for the traders were carving out new states on its periphery, and it was itself becoming subject to slave raids and encroachment. This external pressure weakened the political structures. Rival brothers sought the aid of mercenary traders to promote their cause. The ideological basis of the state was undermined. In a desperate attempt to obtain guns the emperors began to raid for slaves amongst their own people. The empire disintegrated and, in about 1890, the rump of the state became tributary to the trader-state of Msiri.